NUTRITION

By Jean Mayer and Jeanne GoldbergNovember 22, 1987

Should breast-fed infants be given supplements of vitamin D?

Vitamin D supplements are recommended for breast-fed infants. However, in a recent review of infant feeding practices, Dr. Samuel Fomon of the Department of Pediatrics at the University of Iowa pointed out that while vitamin D deficiency was not uncommon in breast-fed infants in the 1920s, it is now rarely seen in breast-fed babies in this country. In nearly all deficiency cases reported, the infant was dark-skinned and had been protected from exposure to sunlight.

Dr. Fomon, an expert on infant nutrition, says the decline of the problem may be related to the fact that the vitamin D content of human milk is influenced by the woman's intake of vitamin D. Today, dairy products and certain other foods are fortified with the vitamin, and many women take vitamin D supplements during pregnancy and lactation. It is worth underscoring that vitamin D is toxic at levels not very far above the Recommended Dietary Allowance. Mothers giving infants vitamin D supplements should use only the amount prescribed by the pediatrician and not a bit more.

The other day I ate in a South American restaurant and tried cassava. It was prepared like french-fried potatoes. Can you tell me what it is and how it relates to tapioca.

Cassava, the product of a perennial shrub, is a starchy edible root shaped like an elongated sweet potato. It is calorically dense; 3.5 ounces contain 120 calories, compared to 105 in the same portion of sweet potato.

Although it is a relatively obscure food in this nation, cassava, also known as manioc, is an important dietary staple in many developing countries. As a source of calories, it has an advantage over other staple crops in that it does not require ideal growing conditions. It can even be cultivated on marginal land. While it does provide necessary calories, it does not furnish much in the way of essential nutrients.

Tapioca is a starch extracted from cassava. Because it tends to create an unpleasant stringy texture in water if used in plain form, a heat process is employed to form it into the pearl shapes with which you are familiar.

Cassava is native to the tropical Americas and has been a dietary staple there for centuries. In fact, evidence shows that it has been under cultivation for at least 2,500 years.